Immunocytochemical Detection of ALK and ROS1 Rearrangements in Lung Cancer Cytological Samples

The detection of molecular alterations such as ROS1 and ALK rearrangements is performed as part of the diagnosis of advanced-stage lung adenocarcinoma. These alterations allow the treatments with tyrosine kinase inhibitors. Cytological samples are very useful as up to 40% patients are diagnosed with this type of sample. Here we describe the immunocytochemistry technique usable to reveal the overexpression of ALK or ROS1 tyrosine kinase receptors secondary to ALK and ROS1 rearrangements, respectively.